The first ever commit to Sentry (via) This is fascinating: the first 70 lines of code that started the Sentry error tracking project. It’s a straight-forward Django process_exception() middleware method that collects the traceback and the exception class and saves them to a database. The trick of using the md5 hash of the traceback message to de-dupe errors has been there from the start, and remains one of my favourite things about the design of Sentry.